基于光电传感器的自动硬币分拣装置

自动硬币分拣装置的基本功能是把常用的不同面额的硬币(1元、5角和1角)进行区分收集。本装置分拣硬币的功能通过光电传感器测量不同面额不同的硬币直径来完成。试验表明,采用光电传感器的自动硬币分拣系统实现了对不同面额硬币的分拣功能。系统体积小、成本低、性能稳定可靠。     

一种全自动硬币分离计数装置的设计

设计一种全自动硬币分离装置,该装置实现硬币的分离、整理、包装和计数,解决了大量硬币的清点问题。通过筛筒,实现1元、5角、1角硬币的成功分离;通过整理仓,实现硬币的归类和整理,并且按照数量进行包装;通过计数筒,实现硬币的清点。     

硬币分拣计数控制系统设计

为解决大量硬币在进行分拣后的计数问题，减轻人工计数的作业负担，同时弥补人工硬币计数易出现差错的缺陷，设计了一种基于单片机的硬币计数控制系统，可同时满足1元、5角、1角三种类型的硬币进行计数作业。该设计采用成本较低且可实现稳定计数的单片机对整体系统进行控制作业，分别对满足硬币计数控制系统实现所需的光电传感器、完整电路模块以及总体的电气控制系统进行设计选型，以提升硬币计数的正确率和效率。     

基于QPD的二维角位移精密测量传感技术研究

为解决二维角位移高精度精密测量的问题,研究了一种基于QPD的二维角位移测量方法。以LED作为光源,低暗电流、高灵敏度的四象限光电探测器作为检测元件,采用光学杠杆式的测角方法形成测量系统。分析了光斑大小对测量结果的影响,并搭建高集成实验系统进行验证。测试实验结果表明:测角分辨力达到1″,在2mrad量程内,非线性度为0.18%,数据采集与传送延时为250μs。该方法可用于精密光机系统,以便高精度实时监测高速运动元件的二维角运动。     

一种混合硬币自动分点装置

考虑到硬币分点过程的难度和复杂性,设计研制了一套针对混合硬币自动分类与清点的机械装置。根据不同面额硬币的直径差异,利用具有振动功能的倾斜滑道对混合硬币进行快速分拣,进入分拣区的硬币按照直径大小依次实现分类回收。通过单片机、压力传感器和C语言编程,开发了具有硬币清点与计数功能的精密电子装置,可对回收的1角、5角及1元硬币进行实时监测,并将清点的硬币数量与金额同步显示于LCD屏上。实测结果表明,该装置具有良好、稳定的硬币分点效能,为硬币分点技术的思路创新提供了有力参考。     

硬币分类、整理、包装机械系统设计研究

传统的硬币处理系统忽略了硬币的真伪检验,且硬币整理计数精准率较低.为了弥补传统硬币处理系统的不足,集中机械、电子等多种专业技术,尝试开发一套硬币分类、整理、包装机械系统.该系统能够利用数字信号处理(Digital Signal Process,DSP)控制器检验硬币真伪,而且可以运用激光扫描统计硬币数量并加以整理,同时...     

星上敏感器空间矢量自准直测量方法及标定试验

针对星上敏感器测量坐标系高精度标定的需求,提出一种空间矢量自准直测量方法,采用光电自准直经纬仪、卫星转台、基准镜阵列和坐标平移系统等,实现立方镜镜面法向矢量之间夹角的高精度自动化测量。给出空间角测量模型,基于误差传播原理推导出误差模型,并证明不确定度上限;仿真分析传感器精度对空间角测量误差的灵敏度,并在此基础上进行误差分配;设计并研制星上敏感器空间矢量自准直测量系统,对光电自准直经纬仪的转角精度、两轴垂直度和整个系统的空间角测量精度等进行试验标定;结果表明,光电自准直经纬仪转角精度优于0.6″、两轴垂直度优于0.2″,空间角测量精度优于3″,验证所提出方法的有效性、误差分配的合理性和设计方案的可行性,可为高精度星上敏感器的自动化测量标定系统的开发和应用提供参考。     

非接触式扫描反射镜转角测量系统

为了提高扫描反射镜转角检测系统的测角范围,建立了基于一字线激光器和线阵CCD的高精度非接触式扫描镜角度检测系统。介绍了检测系统的结构和工作原理,该系统根据激光光斑在CCD上的位置计算扫描反射镜的转角,并利用特殊设计的阵列反射镜增大测角范围。为了降低对加工及装调精度的要求,对系统进行了误差分析,给出了采用多项式拟合法进行角度测量的理论依据。讨论了影响系统检测精度的一系列误差源,计算了系统测量的总误差。最后进行了相关的测量实验。实验结果表明：系统的检测系统分辨率为2.5",测角范围为11°,测角精度可达3",可以满足扫描反射镜对角度测量系统提出的高精度、非接触、大测角范围的要求。     

一种硬币自动清选分离计数机械设计

针对硬币在流通过程中存在不易清点等问题,在原有的硬币清分装置基础上,设计开发了一种新型全自动硬币清选计数的机器。该机器具有设计原理简单,抗振动,抗电磁干扰能力强等特点,且成本低廉。它利用不同币值的硬币的直径大小不同,实现硬币清分;然后通过光敏传感器对硬币数量进行统计,最终实现了硬币清分和计数功能。     

车载经纬仪的测量误差修正

载车平台变形会直接导致经纬仪方位旋转轴线产生倾斜,从而影响经纬仪的测角精度。为补偿测角精度,实现活动站测量,通过球面几何推导了平台变形对光电经纬仪测角误差影响的修正公式,利用光电轴角编码器精度高、采样频率高的特性,测量出经纬仪坐标系倾斜,经过坐标变换推导出经纬仪倾斜角和倾斜方向,该测量装置通过时统终端与经纬仪望远系统同时记录测角数据及倾斜数据,从而对测角误差进行修正。实验结果表明,该方法能够实时有效地补偿因平台变形而带来的测角误差,使经纬仪不落地测角精度控制在20″内,为实现高精度车载光电测量提供了一种有效的途径。     

一种基于棋盘格的高精度分区域相机标定方法

在视觉测量系统中,相机的标定精度至关重要,将影响整个测量系统的精度。针对现有相机标定方法难以兼顾精度和操作复杂度的问题,本文提出了一种基于棋盘格的高精度分区域相机标定方法。首先,将棋盘格置于不同位置,提取不同位置角点的世界坐标和像素坐标,对所有角点用线性变换和非线性最优算法求解出全局标定参数。然后,将角点分为中间区域角点和边缘区域角点,对两区域角点分别标定得到两组分区域标定参数。标定实验结果表明：与全局标定法相比,分区域标定法的图像平均投影误差至少降低16%。该方法操作简单,精度高,可以很好的应用于工业视觉检测。     

形貌视觉测量中立体拼接靶标的设计及应用

设计了一种正六棱柱形状的立体拼接靶标,以靶标侧面6个棋盘格的角点作为全局控制点。基于近景摄影测量技术,建立立体靶标的6个单元模型,通过计算模型内摄站间的相对位姿,推导出棋盘格角点在所属单元模型的局部坐标。以公共棋盘格为中介,确立相邻单元模型的坐标系转换关系。建立靶标的全局坐标系于1号棋盘格,推导该棋盘格平面与其像平面间的单应性矩阵,从而确立全局坐标系和1号棋盘格所处单元模型的坐标系的转换关系。依次递推实现全局坐标系和每个单元模型坐标系的转换,进而计算出全部靶标角点的全局坐标,再经光束平差算法获取精确值。以玻璃表面棋盘格的角点间距作为评价指标,拼接精度优于0.15 mm/m。基于立体拼接靶标的拼接试验表明,实体模型表面4个子区域的局部点云可被精确地拼接成整体点云。与基于全局控制点和平面靶标的拼接方法相比,本方法亦具有更高的拼接精度。     

一种多枚混合硬币处理装置设计及应用实验研究

研制了一种能够高速处理接纳多枚混合币种硬币的自动化装置。该装置应用在金融自助服务终端，需要能够对正常接收的硬币及各种可能的异物进行处理，机构兼容性及控制要求较高。设计了多枚混合硬币的高速分离机构；通过运用PRO／E机构运动仿真，设计了处理异物的闸门传动机构；设计了能够高效控制各个运动部件的控制系统。样机实验表明，该装置结构和工艺设计合理，与驱动部分配合合理，工作状况良好。     

FPGA-based High-precision Measurement Algorithm for the Ultrasonic Echo Time of Flight

Based on the evaluation of advantages and disadvantages of high-precision digital time interval measuring algorithms, and combined with the principle of the typical time-difference ultrasonic flow measurement,the requirements far the measurement of echo time of flight put forward by the ultrasonic flow measurement are an-alyzed.A new high-precision time interval measurement algorithm is presented, which combines the pulse counting method with the phase delay interpolation. The pulse counting method is used to ensure a large dynamic measuring range, and a double-edge triggering counter is designed to improve the accuracy and reduce the counting quantiza-tion error.The phase delay interpolation is used to reduce the quanti-zation error of pulse counting for further improving the time measure-ment resolution.Test data show that the system for the measurement of the ultrasonic echo time of flight based on this algorithm and im-plemented on an Field Programmable Gate Array(FPGA) needs a rel-atively short time for measurement,and has a measurement error of less than 105 ps.     

Using wire electrical discharge machining for improved corner cutting accuracy of thin parts

The wire electrical discharge machining process (WEDM) allows one to achieved ruled surfaces along intricate contours in hard materials. When one intends to use such a machining process, one has to analyze both the magnitudes of the corners’ radii and the corner’s angles that are formed between adjoining surfaces. Some experimental research work carried out unveiled the systematic occurrence of machining errors when WEDM is used to obtain outside sharp corners, especially in small thickness workpieces. A permanent bending at the crest of sharp corners, which leads to a substantial deviation from the prescribed geometrical shape, was found. The deviation form depends on the magnetic properties of the workpiece material. The research was focused on establishing a means for characterizing this shape error. Moreover, the influence exerted by certain factors, such as the corner angle and the thickness of the workpiece on the above-mentioned machining error was quantified.     

Dynamic properties of measuring circuits applied to frequency output transducers

Frequency output measuring transducers transform the measured quantity x into the frequency f or the period T of the output signal. Frequency is usually measured by counting the number of pulses produced by the output voltage during a constant counting time t_c, long enough to minimize a random error. The period is measured by counting the pulses of a reference oscillator in the varying time equal to N periods of the transducer's output signal. Considering the dynamic properties of both measuring chains one may conclude that averaging of the measured occurs, and in order to calculate the dynamic error, an averaging transducer ought to be taken as a reference. The paper indicates that under dynamic conditions the frequency measuring chain may be treated as a really averaging one, the period measuring chain only as an approximately averaging one, and in both cases averaging is not sufficient to eliminate the aliasing error of the sampling procedure. A method for accelerating the measurement and then avoiding the aliasing error is the “one-period method” considered in the paper. The averaging error and delay error of this method are considered in detail, under the assumption that a parameter-controlled oscillator is used as an element of the measuring chain.     

High-speed contouring enhanced with P-H curves

In this paper, Pythagorean hodograph (P-H) curve theory is used for high-speed contouring applications. There are large contouring errors around sharp corners when low-bandwidth servo controllers (such as P-PI control) are used. It is possible to construct a P-H curve in the region of sharp corners in order to decrease the amount of cornering error. The developed algorithm is implemented for various corners with different angles. With respect to sharp tool paths, the total machining time is increased by a small amount, but the cornering error is reduced to the allowable tolerance limit. The results of simulation, such as the total cornering time and the cornering error, are compared with previously published methods. It has been shown that the over-corner P-H approach will substantially decrease the amount of cornering error.     

基于PIC16F886的高速检伪投币系统

为了解决市面上由于货币流动多大而造成无法识别假币的问题,将PIC16F系列单片机结合电涡流传感器技术应用到真假币识别系统设计中。分析并指出了使用PIC16F886单片机作为系统的核心对通过的真币和假币给予相应的数字处理信号,提出了结构简易、价格成本优势明显、检测速度快、采集数据精度高的设计方案;在对同类产品进行比较的基础上,对分辨准确率和识别速率进行了评价。实验结果表明,该系统的真币正确辨识率达100%,假币正确辨识率平均在95%以上,硬币检测速度高达900枚/min以上;并且可以通过调节灵敏旋钮自主改变硬币识别的精度范围,可灵活地应用于公交投币箱、自动售货机、地铁售票机、投币电话、娱乐投币机等不同的投币场所。     

Real-time P-H curve CNC interpolators for high speed cornering

In this paper, real-time Pythagorean hodograph (P-H) curve CNC interpolators are used for high speed corner machining. There are large contouring errors around sharp corners when low-bandwidth servo controllers (such as P-PI control) are used. In order to decrease the amount of the cornering errors, an improved interpolation method is proposed. The first deceleration phase of motion and the over-corner P-H curve constructed for regions with sharp corners are devised by quadratic and constant velocity interpolation algorithms, respectively. The geometric parameters of the over-corner P-H curve and the feed rate along the modified tool path are computed by pattern search algorithm in order to reduce the maximum cornering error. The proposed interpolation algorithm is implemented for symmetrical and unsymmetrical corners. The results of simulation, such as the cornering error and the total cornering time, are compared with previously published methods. It has been observed that the developed over-corner P-H approach can substantially reduce the amount of cornering error.